1. Field of the Invention
The present invention relates mainly to an absorbent article for absorbing and retaining a liquid waste such as menstrual blood and, more particularly, to an absorbent article enabled to absorb the liquid waste effectively in accordance with the motions of a wearer.
2. Related art
In the prior art, there have been a variety of absorbent articles including a sanitary napkin, a pantie liner, a urine absorbing pad and a diaper. These absorbent articles are demanded, when worn, for absorbing the liquid waste reliably in an absorbent core so that the liquid waste may not leak to the outside of the absorbent articles.
Here, the body portion around a discharging part especially around a vaginal opening is different in shape among the states in which the wearer stands, sits down, or closes or opens legs, and especially changes its shape every moment while the wearer is walking. At this walking time, the muscles of the right and left buttocks are displaced transversely or vertically by about 30 mm at the maximum with respect to the longitudinal direction of the body.
As the right and left thighs make motions to intersect each other, more specifically, the muscular tissues of the thighs repeat relaxations and tensions. Of these muscular tissues, the inguinal ligaments on the inner sides of the thigh portions are so associated with the movements of the thighs as to move within a predetermined range on the inner sides of the thighs.
At this time, the muscular tissues in the vicinities of the ligaments move so that the skin surfaces of those portions sink from the surrounding skin surfaces. This sinking phenomenon occurs for time so that it is caused to restore its original state by the relaxations of the muscular tissues. Where the relaxations/tensions of the thighs are intermittently repeated as at the walking time, the sinking phenomenon also occurs intermittently. This sinking phenomenon occurs not only at the walking time but also at the time of opening/closing the legs or at the time of shifting the sleeping positions. This sinking portion fails to come into close contact with an absorbent core of the absorbent article so that a clearance is frequently established to leak the liquid waste from the clearance.
As the sanitary napkin to be brought into contact with the discharging part, a sanitary napkin, in which an absorbent core can move from a liquid-impermeable back sheet toward a wearer, is disclosed in International Unexamined Patent Publication No. 6-502336 (i.e., WO92/07535), for example. In Unexamined Published Japanese Patent Application No. 4-164446, on the other hand, there is disclosed a sanitary napkin which is provided with an upper absorber over a lower absorber. In these napkins, the upper absorbent core can easily come into close contact with the recess of the discharging part to prevent the leakage better than the ordinary napkin. In these napkins, however, the motions of the wearer cannot be followed to establish a clearance from the recessed portion.
In Unexamined Published Japanese Utility Model Application No. 7-33315, there is disclosed an absorbent article (or a sanitary napkin) which aims at preventing the leakage of a menstrual blood even when the wearer freely moves around. This absorbent article includes an upper napkin and a lower napkin, of which the smaller upper napkin is positioned at the central portion of the larger lower napkin whereas this lower napkin is attached to a pair of (i.e., righthand and lefthand) elastic members extending longitudinally from the two end portions of the upper napkin. These upper napkin and lower napkin can move relatively freely without restraining each other. A similar technique is disclosed in Unexamined Published Japanese Patent Application No. 11-104168.
In the napkin of the above-specified Application, the upper napkin can come reliably into close contact with the discharging part when the wearer stands upright. However, the upper napkin is always tensed forward and backward by the elastic members extending forward and backward from the two end portions of the upper napkin and connecting the upper napkin and the lower napkin. Therefore, the upper napkin can not move forward or backward freely and independently of the lower napkin. As a result, in the case where the lower napkin being applied to an underwear is deformed to have one side potion forward and to have the other side portion backward due to the opposite motions of the right and left legs as the wearer walks, the upper napkin being close contact with the discharging part will be influenced by the deformation of the lower napkin to cause a twist. Therefore, a clearance is established between the discharging part and the upper napkin so that the leakage occurs.
The invention has an object to provide an absorbent article which is excellent in the followability to the motions of a wearer while keeping a high contact with a discharging part.
According to a first aspect of the invention, there is provided an absorbent article comprising: a support body for confronting an external wear; a liquid absorbing member positioned on the liquid-receiving side of the support body; two side wall sheets disposed on two sides of the support body lying opposite one another in the widthwise direction, the side wall sheets being separated from one another in the widthwise direction and being longitudinally attached at their root ends to the support body; and a connecting sheet connecting the two side wall sheets, wherein the side wall sheets are individually subjected to elastic shrinking forces in the longitudinal direction for shrinking to raise the free ends thereof from the support body to the liquid-receiving side, and the liquid absorbing member is supported by the connecting sheet so that the liquid absorbing member is movable over the support body while being unattached directly to the support body.
According to the first aspect of the invention, the liquid absorbing member is supported while floating from the support body by the connecting sheet extending between the side wall sheets (or side walls formed therefrom to rise to a wearer), so that the liquid absorbing member can move freely and independently of the support body in a proper moving range in the longitudinal and widthwise directions over the support body. Moreover, the side walls on the right and left sides of the liquid absorbing member can move relatively independently from each other. In addition, the liquid absorbing member is not attached directly to the side walls but is attached indirectly (or connected) through the connecting sheet to the side walls. Even if the liquid absorbing member is deformed, therefore, the deformation force is hardly applied to the side walls so that the shape of the side walls rising to the liquid-receiving side is hardly destroyed. As a result, the liquid absorbing member can fit reliably on the discharging part even when a wearer moves so that little liquid waste such as menstrual blood leaks. In addition, due to its followability to the motions of a wearer, the liquid absorbing member is prevented from being rubbed against the skin of a wearer harshly so that a comfortable wearing feel can be achieved.
It is preferred that the connecting sheet has a stretchability in the longitudinal direction.
The liquid absorbing member may include an absorbent core and a liquid-permeable sheet covering at least the liquid-receiving side surface of the absorbent core, and may be attached to the liquid-receiving side surface of the connecting sheet. Alternatively, the connecting sheet may be liquid-permeable, and the liquid absorbing member may be attached to the support body-facing side surface of the connecting sheet.
It is preferred that longitudinal front and rear end portions of the side wall sheets are wholly attached to the support body to exert forces to curve the support body in the longitudinal direction so that the liquid-receiving side is recessed.
For exhibiting the elastic shrinking forces in the longitudinal direction, the sidewall sheets may be formed with corrugations repeated in the longitudinal direction and/or elastic members may be attached to the side wall sheets.
In the case where the elastic members are provided, each side wall sheet may be provided with a plurality of elastic members extending in the longitudinal direction and arranged at a spacing therebetween from the root end to the free end.
The side wall sheets may extend in a zigzag shape or a corrugated shape from the root ends to the free ends.
The connecting sheet may be attached to the side wall sheets respectively at a position between the free end and the root end, and the side wall sheets may be extended at their free ends farther toward the liquid-receiving side than the attached portions to the connecting sheet so that leakage preventing cuffs may be formed of the extensions of the side wall sheets from the attached portions. Alternatively, it is also possible to provide leakage preventing cuffs separately of the side wall sheets.
In the case where leakage preventing cuffs are formed of the extensions of the side wall sheets, it is preferred that elastic members are attached to the free ends of the side wall sheets for exhibiting elastic shrinking forces in the longitudinal direction.
Another absorbent member may be provided on the support body to confront the liquid absorbing member supported by the connecting sheet.
According to a second aspect of the invention, there is provided an absorbent article comprising: a support body for confronting an external wear; a liquid absorbing member positioned on the liquid-receiving side of the support body; and a side wall sheet having two side portions and a central portion therebetween in the widthwise direction, the side wall sheet connecting two side portions of the support body lying opposite one another in the widthwise direction, with its two side portions being individually attached to the two side portions of the support body but with its central portion being unattached to the support body, wherein the side wall sheet is subjected to an elastic shrinking force in the longitudinal direction for shrinking to separate its central portion from the support body to the liquid-receiving side, and the liquid absorbing member is supported by the central portion of the side wall sheet so that the liquid absorbing member is movable over the support body while being unattached directly to the support body.
The absorbent article according to the second aspect of the invention can also achieve the same functions and effects as those of the absorbent article according to the first aspect of the invention.
It is preferred that the side wall sheet has a stretchability in the longitudinal direction.
The liquid absorbing member may include an absorbent core and a liquid-permeable sheet covering at least the liquid-receiving side surface of the absorbent core, and may be attached to the liquid-receiving side surface of the central portion of the side wall sheet. Alternatively, the side wall sheet-may be liquid-permeable, and the liquid absorbing member may be attached to the support body-facing side surface of the central portion of the side wall sheet.
It is preferred that longitudinal front and rear end portions of the side wall sheet are wholly attached to the support body to exert a force to curve the support body in the longitudinal direction so that the liquid-receiving side is recessed.
For exhibiting the elastic shrinking force in the longitudinal direction, the side wall sheet may be formed with corrugations repeated in the longitudinal direction and/or elastic members may be attached to the side wall sheet.
In the case where the elastic members are provided, each side portion of the side wall sheet may be provided with a plurality of elastic members extending in the longitudinal direction and arranged at a spacing therebetween toward the central portion of the side wall sheet.
The side portions of the side wall sheet may extend in a zigzag shape or a corrugated shape toward the central portion of the side wall sheet.
Leakage preventing cuffs may be provided on two widthwise sides of the liquid absorbing member to rise toward the liquid-receiving side.
Another absorbent member may be provided on the support body to confront the liquid absorbing member supported by the central portion of the side wall sheet.